1.   Blood tests were important because they were the only way for doctors to detect high liver enzyme levels, a warning sign of possible liver failure.

2.   High liver enzyme levels, found in routine tests of patients on the drug, can be a sign of liver damage.

3.   His blood showed highly abnormal liver enzyme levels, the doctor said.

4.   However, my liver enzyme levels had returned to near-normal levels.

5.   Those identified as being in high risk groups should have a blood test to determine liver enzyme levels.

6.   Unfortunately, there is no easy way consumers can gauge their enzyme levels.

7.   Her enzyme levels had returned to normal by time she left the hospital following the tests, the Inquirer reported.

8.   The top fifth of the men with the highest enzyme levels had twice the risk of those who ranked in the bottom fifth.